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The Heisenberg Uncertainty Principle

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1. The zeroth law of thermodynamics recognizes systems which are in thermal equilibrium with each other, and thus it supports the notion of heat.

Nathan runs his thumb along the edge of a blade.

“I don’t understand why you need that stuff,” he says to Spencer, who is flicking a needle with a thin, elegant forefinger. Spencer doesn’t dignify him with a response, but his expression is similar to that of a child being lectured by an adult whose intelligence he is not entirely convinced of. It’s an expression Spencer’s had a lot on his face, lately.

He puts the knife back down on the table, leans back in the chair, looks over at Spencer. Spencer, who’s the picture of a mild-mannered graduate student, golden hair falling over his face, corduroy and ugly seventies shirt, except for the belt twisted around his bicep. It’s late afternoon, but the curtains are pulled shut. He can hear children playing outside. A thin blade of light falls across Nathan’s leg, cutting it in two. He drums his fingers along the table, watches, fascinated, as the needle slides into Spencer’s arm, biting his lip as he sees a flower of blood burst and swirl in the barrel, before Spencer depresses the plunger and leans back. Nathan watches him, watches as his head droops onto his chest, his entire body relaxing, loosening: opening, almost. He tilts his head towards Nathan, finally, but he’s looking through him, not at him. The bitchy defiance has filtered away, leaving a sort of blissed-out blankness.

Twenty minutes pass. Nathan’s picked up the knife, compulsively running his thumb down it. He’s sort of bored, sort of excited: he knows what’s coming next. Spencer’s got a wide, blurred smile on his face, lost in the networks of his mind. His arms are folded loosely in his lap; the belt’s slipped down his arm, curling on the floor like a dead snake. Aside from that, the room is spotless. Nathan makes sure of it. He can’t abide dirt, and lately Spencer hasn’t exactly been focused on cleaning. There is a small trail of blood down Spencer’s arm.

Nathan’s painfully turned on at this point, but then, he always is by now. The delicate tipping point where he’s too horny to feel the shame that’s become a Pavlovian response to any intimation of erection. There’s a red mark in his thumb from where he’s been rubbing the serrated blade. He picks it up, walks over to Spencer, crouches in front of him. Takes his arm and runs the knife down it, pressing lightly, scraping the blood off it. Spencer flinches slightly.

Nathan stands up, walks behind him, leans in until his face is beside Spencer’s. Grabs a handful of his hair, forcing him to lean back, exposing his throat. His thin voice is loud in the stagnant quiet. “Spencer. I don’t understand why you need it.”

He feels Spencer swallow; feels the heat he radiates. He runs a finger through his hair, down his neck.

“I think you do, Nathan,” Spencer says, finally, his voice sandpapery. Nathan pulls his hair a little harder.

“Explain it to me, then.”

“Have you ever wondered,” Spencer says, and his voice is dreamier now, faraway, as though Nathan was hearing his voice over a bad telephone connection, seas and seas away, “Have you ever wondered why the words scatology and eschatology are so closely related?”

It’s always the same with him. Cryptic. At a certain point, he gets tired of dumbing himself down, the way he constantly has to, tamping down the teacher’s-pet instincts that saved him as a child. Nathan waits.

“The basic disconnect between body and spirit, that’s what I’ve always thought it’s about. The spirit, attempting to transcend. To be free. Anchored to the body. I’ve always thought that true freedom would be a state of pure logic, but I suppose that’s just me.”

Nathan pulls the knife out of his pocket, runs it along Spencer’s shoulder, through his thin shirt. His shoulder is bony.

“Eschatology is the final and ultimate death of everything. Death and disease. We’re all trying to forget that our bodies aren’t perfect machines, they’re flesh and blood and guts, they’re sex and shit and sweat. They’re scatological, they need fuel and they create waste. They break. It’s this breaking I think you’re attracted to, Nathan. Scatology reminding us of the inevitable eschatological end of the body. An inevitable function of the body is both shit and death. And sex, I suppose. Yeah.”

Nathan presses his lips to Spencer’s neck, runs the knife further up his shoulder until it rests in the hollow of his clavicle.

“And this is something we spend our lives obsessed with, and simultaneously trying to hide from. Does that answer your question?”

“Not really.”

“We’re all trying to escape ourselves some way. We all deal with being flesh as well as we can. We all have different ways.” Spencer turns his head until his sharp cheekbone is pressed to Nathan’s nose. He smells stale. Nathan presses the knife down, very lightly. Testing him.

“Do you understand now?”

Nathan lets his hair go. Stands up, paces around, and climbs on top of Spencer, until they are chest to chest, nose to nose. Spencer doesn’t make eye-contact: even high, he has these boundaries, this very smallest shred of self-preservation. Nathan’s hot thighs bracket his, on the couch. Spencer makes no effort to hold him there, staring into space: almost like he’s ignoring him.

Nathan trails the knife back up Spencer’s chest, very slowly, and Spencer smiles, his sweet blurry smile he uses on everyone, and says, “I thought you would.”

Spencer’s so hot he burns. His blood is fire, and Nathan kisses each cut he makes, trying his best not to get carried away, so nobody’ll get suspicious. “Don’t you see,” Spencer says, over and over, “It’s all death, it’s always death, it’s all I ever see. I’m surrounded by it. I try and try, and I can’t stop it.” He arches under Nathan and his knife, the sounds he makes somewhere between pain and pleasure, and they writhe together in the dim half-light of the dead afternoon. All the while whispering things Nathan is too far gone to hear.

Later, in the bathroom, Nathan cleans the cuts off as best he can. Spencer pushes sweaty hair off his forehead, looks around him blearily, but is still just orbiting the earth. The fluorescent light picks out the boniness of his face, the black hollows beneath his eyes, the leached waxiness of his skin, makes him unattractive: Nathan feels revulsion, momentarily, of which he is later ashamed.

And Nathan, well, he feels disgusting, vile: he stares at the cuts across Spencer’s chest, wonders why he’s like this. They’re both sweaty and bloody and bathed in light that’s far too strong, that hurts their eyes. He stares in the mirror, at his dark hair plastered to his forehead, the fine damp gold of Spencer’s hair bright next to him. Bright and dark. Matching pale faces. He wets a cloth, drags it across Spencer’s arcing ribs, and Spencer snaps back suddenly, looking pissed off, and jerks away from him. And this is always how it goes, too: Nathan trying to make amends, and being refused. As if this one action, this attempted care-taking, is insincere (and Nathan can see how it looks that way: how often do sadists really want to wash the blood from their victims?) and just his cowardly attempts at absolution: but he wants to help. The two urges are not incompatible. Right?

“I don’t think you knew what I really meant,” Spencer says suddenly. He dabs at his chest, delicately, wincing. He looks like he’s taking care of a papercut.

“Sorry?” Nathan feels infinite tenderness for him, now that the darkness has lifted temporarily; now is when he can be a good man, now is when he can love the right way, cleaning the wounds he created. Now is when they can both be clean. He presses a kiss to Spencer’s temple; Spencer does not acknowledge him, swipes at a trail of blood running down his stomach. His demeanour is that of a snotty academic being bothered by an irritatingly inept student: this half-hearted condescension is his way of pulling back, getting his bearings again. Nathan grovels and he retreats. His pupils are huge in the thrumming fluorescence.

“Us. This. Everything. It’s like – it’s like thermodynamics,” Spencer says, to his reflection.

“What do you mean?”

“We’re in equilibrium,” Spencer says. “Can’t you tell?”

2. The first law of thermodynamics distinguishes between two kinds of physical process, namely energy transfer as work, and energy transfer as heat. It tells how this shows the existence of a mathematical quantity called the internal energy of a system. The internal energy obeys the principle of conservation of energy but work and heat are not defined as separately conserved quantities. Equivalently, the first law of thermodynamics states that perpetual motion machines of the first kind are impossible.

When Spencer’s father left, his mother made a list called Proverbs for Paranoids and stuck it on the fridge:

1.You may never get to touch the Master, but you can tickle his creatures.
2. The innocence of the creatures is in inverse proportion to the immorality of the Master.
3. If they can get you asking the wrong questions, they don’t have to worry about answers.
4. You hide, they seek.
5. Paranoids are not paranoids because they’re paranoid, but because they keep putting themselves deliberately into paranoid situations.

He was a child, and he didn’t know why his father was gone, and he kept getting the shit kicked out of him for what seemed to be no good reason, and this seemed like a fairly good life-guide; paranoia, at least, guaranteed that there was some kind of system out there, that someone was pulling the strings and it wasn’t just all completely arbitrary. He was used to feeling like the world was against him: he hid, in the library or the stairwell or beneath the bleachers, but they’d always come looking for him, and it seemed easier to accept some kind of sinister Other which felt nothing than to ask why.

His mother started telling him stories about the Others, about vast machines controlling them, about lobotomies and mind-control and the inescapable darkness encroaching on all sides. It’s you and me, kid, she’d say, holding him a little too tight. The stories gave him nightmares. She stopped reading to him: they had gotten to the books, and the messages were encoded there. He asked if he could help solve it – he was fluent in several languages at that point – but she refused. It was her job to protect him from them. The curtains were always drawn. Spencer began taking money from her purse for food; frequently when there was no money he just did without, curled in on himself in the library, trying to ignore the hunger pains. Proust and Chaucer grew dusty, and the television was always on, tuned to an empty channel. His mother would make him watch the static with her for hours, trying to find some kind of pattern in the endless white hush.

There’s nothing there, mom, he’d say, pleading. It’s all meaningless, it’s just white noise. But she’d clutch his wrists so hard it hurt and say, her voice harsh and raw, there’s no such thing as white noise, Spencer, there’s no such thing as meaningless, it’s just information they are trying to keep from us.

It’s just a random dot pattern, mom.

Aha, Spencer, but what happens when you connect the dots? What happens then?

She began to only let him out of the house at specific intervals, in case they were watching. They got visits from officials once or twice, but she was well-respected and he was such an adorable little boy, and so thoroughly good at faking it by then, that nothing ever came of it. He lived in a shadowy half-world where either they were real, or his mother was crazy and there was no real pattern to anything. He wasn’t sure which was worse – and then, of course, he had his own them to deal with in school.

It was when she refused to come to his high school graduation that he realised that there was something wrong with his mother. He supposes at least he didn’t have any friends he had to lie to. And then Cal Tech came swooping to the rescue, and he was spirited, age thirteen, out of the dark house with the crackling static and closed curtains, to California, and the beach, and the sea air, and – freedom. Autonomy. No them lurking in every shadow, in static and white noise, in circuits and wires, round every hallway and down every street. People leave him alone here, and it’s – it’s nice. Of course, he worries about his mother, about whether she’s left the house, about whether she’ll ever leave the house again, but here there is only him and his books. It’s a freedom he’s never known before. The freedom of being alone, self-enclosed, a perfect system.

And then puberty hits, and he is no longer a perfect system. It’s messy and ugly and he hurts constantly, and if he thought he felt awkward and alone before, well, this is nothing. He never thought anything could make him nostalgic for high school, but this – this is disgusting. Spencer’s always considered himself a walking brain, more or less, when he even thought about it, and now he’s thinking about himself more or less constantly, his voice, the way his hands are too big, the hair that’s started growing, the sheer mindless animalism of the whole sordid mess. Before, he felt nothing particular about himself; now, he feels alienated from himself, feels trapped and degraded by mindless illogical flesh, and hates even more that he’s obsessing over it so much. He’s got so much to do, so much to read, and he doesn’t have time for this, he doesn’t want this distraction, these dreams, the sudden pull towards other people, towards, distressingly, both men and women, which doesn’t particularly bother him but is just yet another thing that makes him different – the sudden and inexplicable role theyhave begun to play in his life.

It’s not as if he was a robot, as a child, but he never related to anyone, except his mom, and it never bothered him that he didn’t relate to anyone, but now he thinks – well, now his mother is clearly mentally sick and he feels the tearing ache of loneliness for the first time, cloistered away in his small dorm room with its stacks and stacks of books. He feels – lacking, in a strange, sad way he never felt before. Properly aware of himself, he sees now what was so repellent to others. He’s awkward and skinny and spotty, greasy-haired, hiding behind glasses and badly-fitting clothes, a freak. He feels his body betraying him, finds himself watching girls as they go past, watching boys, and wanting, in a pathetic, urgent sort of way, the way he’s never wanted anything before. His dreams are filled with frantic curves and angles. Sweat and sex. He washes his sheets himself. He feels utterly out of control.

And yet, just as he’s being confronted with himself as an actual human being, he finds it even more difficult to relate to other people. Now, he’s got all these vague and forceful feelings he can barely make sense of, let alone define, and it seems like it’s just another reason he’ll never be able to interact with people normally, because he’s now at the age where your looks and your charm and your emotions are important, and he just can’t deal. It’s like – it’s like his body’s trying to make him one of them, and he’s trying his hardest to resist.

And the thing is – people are just so much work. Even his mother is work now, and she was the centre of his universe not so long ago. It’s – well, he’s heard the metaphor ‘like a test I never studied for’ and always felt mildly smug about how that didn’t apply to him, but he’s beginning to understand it now. So he conserves his energy, and ignores his body, and does his work instead.

The dots never connect. The longing never goes away, exactly, but it gets easier to ignore after awhile.

The first time he meets Nathan, he sees – a kid who reminds him of himself, a little, when he was unsure and knock-kneed and scared (even more so). He stares at Spencer’s feet and his eyes skate over his collar and across his face until finally he can look Spencer in the eyes, and he looks – scared. Shy. Like Spencer used to look. That scared look never seems to quite leave Nathan’s face; he looks like he’s pleading against a verdict he doesn’t even understand. He looks hunted.

Spencer looks at Nathan’s face, and sees that Nathan is like him, like his mother: that he sees them, lurking in faces and static, that he is pursued by forces he cannot comprehend.

And then they catch up with Spencer. And then he’s somehow become the kind of person who shoots up in the bathroom stall at work to avoid collapsing inward like a dead star, and as he pushes the needle into his vein he thinks, well, it would be nice to know that the fucking dots even exist, because that would imply there’s some kind of order. Paranoia is seeing a pattern that isn’t there, but – what if there’s no pattern at all? Is that worse, or is that freedom? He’s always lived by the rules, and now look at him playing the bad boy, and it’s – well. This is the first time, ironically, he’s really felt in control of things. And if he’s breaking the rules, nothing’s happening, is it? And what happened to him, was that random, or just –

He forces himself to stop when he realises he sounds exactly like his mother. He thinks of Proverbs for Paranoids stuck on the fridge, about television static, and chaos, and realises that – scariest of all – they can be chaos. They can be anything, anything at all. Maybe their strength is that they aren’t organised like his mother thought. Maybe their strength is that they are arbitrary, and they’re not even out to get you – they just don’t care at all.

When he gets home that evening, Nathan Harris is sitting outside his door.

Who, exactly, is pulling the strings here?

3. The second law of thermodynamics distinguishes between reversible and irreversible physical processes. It tells how this shows the existence of a mathematical quantity called the entropy of a system, and thus it expresses the irreversibility of actual physical processes by the statement that the entropy of an isolated macroscopic system never decreases. Equivalently, perpetual motion machines of the second kind are impossible.

“The term entropy was coined in 1865 by Rudolf Clausius based on the Greek ‘entropía’, a turning toward.”

This is one of Spencer’s favourite subjects when he’s high. Nathan tightens his grip on his arm, shifts closer, trying to remind him that he’s not alone. He’s lost track of time, but the sky’s getting lighter around the edges, so he guesses the night is almost over.

“Turning towards what?” Nathan says. He releases Spencer’s arm, brushes his thumb along his throat, touching his jaw. There are only limited windows in which he’s allowed to touch Spencer, usually when he’s high. In the mornings, he reaches for Spencer, tries to kiss him, to touch him, and Spencer flinches away skittishly, shrugging him off. This is how it always goes: at night, Spencer’s passive and a little desperate, and he lets Nathan do what he needs to do; in the morning, he’s – not frightened exactly, or no more so than he usually is around Nathan, but distant and jumpy. It’s like every morning he realises exactly what he’s doing, and every morning Nathan’s heart breaks and he thinks, this is it; this is when it will finally end. But if Spencer doesn’t encourage him, exactly, he never stops him either, and Nathan supposes that’s the best someone like him can do.

And besides – he loves him, in whatever sad and broken way he can manage. He loves Spencer so much it hurts. It hurts them both. And Spencer looks at him, in this way that – it’s hard to tell if it’s disgust, or fear, or just a lack of recognition. He touches Nathan sometimes, hesitant, as if checking that he’s real. He accuses Nathan of having come for him, whatever that means, and Nathan says, yes, I did come for you, of course I came for you, this isn’t an accident, and Spencer looks alternately scared and victorious.

“Chaos,” Spencer says. “It’s evidence of the irreversibility of physical processes. You’d think that it’s purely mechanical, but it isn’t. It’s everything.”

Nathan doesn’t say anything. He kisses Spencer’s temple.

“Our own irreversible physical processes: sex and death. The great deciders. Eros and Thanatos. Scatology and eschatology. And then chaos.” Spencer shifts, looks at Nathan, his eyes searching. “Do you see? It’s a part of the system. We can’t stop it. Chaos comes for everything in the end. It’s all the same thing. Sex and death.”

Once, Spencer had come home from work and, slinging his satchel aside, pushed Nathan up against the wall so hard it hurt. He’d raked his nails down Nathan’s side and his teeth left red marks on Nathan’s neck, and afterwards he said, do you ever feel like there’s some dark thing out there controlling everything, and Nathan, touching a long thin cut he’d left down Spencer’s thigh, had said, yes, every day.

“The system is that the system always breaks. It’s – you can connect the dots, but you’ll never understand the picture. Entropy is just unavailable information, information that’s being kept from us. Chaos is a lack of knowledge, but – we base everything on the supposition that all information is coherent, but – how do we know that’s even true, Nathan?”

“It doesn’t have to be all chaos,” Nathan says. “It can’t all be chaos.” He feels sick, saying this while he strokes the scars he’s inflicted on the only person he’s ever really loved, but – but he can still hope, right? He might be a monster, but has the right, at least, to hope that there is something good out there – something better than him. He’s in love with something better than him. “You’re – you’re good.”

“Everything and everyone devolves,” Spencer says, his eyes skittering off along the ceiling. “I’m not an exception.”

Nathan tenses, tightening his grip on Spencer’s arm; Spencer flinches, looks at him, smiles something that’s not really a smile by any stretch of the imagination.

“Then what am I?” Nathan says. “What am I, Spencer?”

“I don’t know, Nathan. What are you?”

4.The third law of thermodynamics concerns the entropy of a perfect crystal at absolute zero temperature, and implies that it is impossible to cool a system to exactly absolute zero, or, equivalently, that perpetual motion machines of the third kind are impossible.

Nathan comes across a phrase, underlined, in one of Spencer’s books:

“Faust did not want to know evil in order to rejoice that he was not so bad (only the bourgeois does that) but on the contrary he wants to feel all sluices of sin opening within his own breast, the whole immense realm of possibilities, nothing else matters compared with that. He wants to be disappointed in his expectations...”

He wonders, again, what exactly Spencer’s motivations are here. He wonders what he’s doing here. But when he got out of the hospital, he could feel the strength of their bond, could feel himself being drawn inexorably west, to Virginia, to him. To Spencer Reid, and maybe to some kind of understanding of himself, of whatever dark and insatiable forces make him this way. He came to find his saviour, sort of, if you can say that kind of thing nowadays – he came to find the kind of person he could have been in another life.

When Spencer had come home and seen him there, the first thing he’d said was, “Am I hallucinating?” which now that he thinks about it. There are books everywhere about chaos theory, about conspiracies and cults. About entropy and psychology. He wonders what, exactly, is going on in that beautiful mind. He’d tried to probe, once, but Spencer had given him an odd look and said, Nathan, they’ve got you asking the wrong questions.

Who’s they. Spencer. Who’s they?

You know.

The television, when he turns it on, is tuned to static. Their conversations have become more and more disjointed, odder, like pieces from different jigsaws all forced together. Spencer says, it was only when I became a real human being that I realised, and he trails off, and Nathan says softly, but you were always a human, and Spencer shakes his head. No, he says, I was rational, once, I know it. And he offers himself up for punishment every night.

I’m evil, Nathan says, and Spencer says: show me.

The curtains are nearly always shut now. There’s a smell of damp. They’re both pale, and Spencer’s always exhausted, and Nathan doesn’t dare to go outside because he’s scared of what he might do. It’s laughable, sort of: being in love means you’re not supposed to want to fuck other people, but Nathan’s infidelity is that he still wants to cut the girls who walk down the street at night.

What are we doing, he asks. Where is this going, and Spencer says, do you know what the Heisenberg uncertainty principle is?


Well, the Heisenberg uncertainty principle states precise inequalities that constrain certain pairs of physical properties, such as measuring the present position while determining future momentum; both cannot be simultaneously done to arbitrarily high precision. That is, the more precisely one property is measured, the less precisely the other can be controlled or determined.

What does that mean?

In other words, you either know where you are or where you’re going, but never both.

There’s this weird list called Proverbs for Paranoids that appeared on the fridge one day. Reading it gives Nathan the skeeves. He tries, desperately, to cheer Spencer up: cooks him food, which goes uneaten, buys him books, which are consumed rather than read, talks about nice things (sometimes he makes his own skin crawl, trying to pretend like he knows what nice is). He asks Spencer how work went, and Spencer gives him a body-count, and Nathan tries not to ask for too much detail.

You like magic, right, he says one day, desperate by now. What’s your favourite kind?

Sleight of hand.


Well, Spencer says, I like it because you get to pretend you’re subverting the system. Magic is the art of deception, of appearing to break the laws of physics, of motion, of reality. Of appearing to swallow swords and inflict pain on oneself, and walking away without a scratch.

Nathan rubs his thumb over the blade. Feels it all starting again.

It’s – illusion is as close as you can get to freedom. Because you can only ever trick them.

Spencer, he says, his voice cracking. Feeling desperate now. The blade gleaming in the dull light. There’s no them.

You don’t get it, Spencer says.

Nathan throws the knife down, angry now, and says, what’s wrong with you? Why are you letting me do this to you?


He wants to hurt Spencer now, but for different reasons. It’s always fucking entropy with you, he snarls. What is it this time. Do me a favour and explain it for me.

Well. You and I are a system, you see. We create heat. And entropy means the system cannot cool – we’ll always generate heat, you and I, do you see? Chaos is what’s keeping us together. Entropy. It’s always entropy, in the end, Nathan, don’t you see?

Spencer, Nathan says, so frustrated he could cry, we are not a system. We’re people, we aren’t math, we aren’t thermodynamics. You’re a human being. You’re not a system. There’s no big system controlling us all.

Are you really that sure? Spencer asks him. He gestures to the knife on the table between them. Are you absolutely sure?